Antarctica and sea level riseWhy is it important?

Antarctic ice shelves

Ice shelves, which are the floating parts surrounding Antarctica, play an important role in the ice sheet's contribution to sea level rise. Ice shelves act as Antarctica’s border control: by providing resistance to the ice, they prevent the land ice to enter the ocean and as such slow down sea level rise.

Melting ice shelves

These ice shelves can melt at the top due to atmospheric warming or at the bottom due to warm ocean water. When this happens, they become potentially unstable and can collapse. Such a collapse has occurred several times over the past decades in West Antarctica.

Subsurface lakes

Water flowing and draining

Warm micro-climate ...

By combining our field measurements with climate models and satellite data we can explain why this micro-climate occurs. It’s the result of strong downslope (katabatic) winds that originate in the ice sheet’s interior. These winds mix the warmer air in the upper atmosphere with the cold air at the surface, creating these warm conditions and enhancing melt in summer.

... result in melt

Is East Antarctica in danger?Conclusions

The implications of our study are twofold. Firstly, these features are exceptional for East Antarctica, as they are usually only found in Greenland or West Antarctica. This suggests that surface meltwater processes are important on East Antarctica as well, which is usually considered too cold for these processes to occur.

Is East Antarctica in danger?Conclusions

Secondly, although East Antarctic ice shelves do not show signs of instability right now and climate is still relatively stable, we have pinpointed a potential ‘weak spot’ of these ice shelves. In the future, warmer climates undoubtedly intensify melt, increasing the risk of East Antarctic ice shelves becoming unstable, collapsing, and invoking ice loss from East Antarctica

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Acknowledgements

This research is the result of an enormous team effort of an international team consisting of Jan Lenaerts, Stef Lhermitte, Reinhard Drews, Stefan Ligtenberg, Sophie Berger, Veit Helm, Paul Smeets, Michiel van den Broeke, Willem Jan van de Berg, Erik van Meijgaard, Mark Eijkelboom, Olaf Eisen and Frank Pattyn.

Field data were collected in the framework of the BENEMELT project, in collaboration with the BELSPO project ICECON. BENEMELT benefits from the InBev-Baillet Latour Antarctica Fellowship, a joint initiative of the InBev-Baillet Latour Fund and the International Polar Foundation (IPF) that aims to promote scientific excellence.

We gratefully acknowledge field support from IPF, BELSPO, AntarctiQ, the Belgian Polar Secretariat and the Belgian military.